There are known various processes for producing olefin compounds by dehydration reaction of alcohols. For example, Patent Literature 1 discloses a process for producing an olefin compound by subjecting a tertiary alcohol to dehydration reaction in a gas phase at a temperature of from 200 to 400° C. in the presence of an aluminosilicate as a solid catalyst.
In addition, Patent Literature 2 discloses a process for producing ethylene by subjecting ethanol to dehydration reaction in a gas phase in the presence of a catalyst prepared by adding a phosphate to an active alumina.
On the other hand, the present inventors have found that olefins can be produced for a short period of time with a high yield by subjecting a long-chain alcohol to liquid-phase dehydration reaction using a catalyst having specific weak acid sites, such as γ-alumina, and previously filed a patent application relating thereto (refer to Patent Literature 3).